They are like Google; they give guidelines but don't tell you exactly because they don't want people to manipulate it.
A relevant snippet:
"The scoring seeks to place players into servers that already have others players in them. This is positive feedback: once one server (by the luck of the draw) gets its first few players, it can continue to receive players while the other, identical server, receives none. The reputation scoring system generates similar positive feedback on a slower time scale. The best way to kickstart your server is to get some people to connect to it."